The American legal system, as well as some other legal systems around the world, relies heavily on written judicial opinions—the written pronouncements of judges—to articulate or interpret the laws governing resolution of disputes. Each judicial opinion is not only important to resolving a particular dispute, but also to resolving all similar disputes in the future. This importance reflects the principle of American law that the judges within a given jurisdiction should decide disputes with similar factual circumstances in similar ways. Because of this principle, judges and lawyers within the American legal system are continually searching an ever-expanding body of past decisions, or case law, for the decisions that are most relevant to resolution of particular disputes.
To facilitate this effort, companies, such as West Group (formerly West Publishing Company) of St. Paul, Minn., not only collect and publish the judicial opinions of jurisdictions from almost every federal and state jurisdiction in the United States, but also classify the opinions based on the principles or points of law they contain. West Group, for example, classifies judicial opinions using its proprietary Key Number™ System. (Key Number is a trademark of West Group.) This system has been a seminal tool for finding relevant judicial opinions since the turn of the century.
The Key Number System is a hierarchical system of over 400 major legal topics, with the topics divided into subtopics, the subtopics into sub-subtopics, and so on. Each topic or sub-topic has a unique alpha-numeric code, known as its Key Number classification. Table 1 shows an example of a portion of the Key Number System for classifying points of divorce law:
TABLE 1Key Number hierarchy and corresponding Topic DescriptionsKeyNumber ClassificationTopic Description134Divorce134VAlimony, Allowances, and Property Disposition134k230Permanent Alimony134k235kDiscretion of CourtAt present, there are approximately 82,000 Key Number classes or categories, each one delineating a particular legal concept.
Maintaining the Key Number System is an enormous on-going effort, requiring hundreds of professional editors to keep up with the thousands of judicial decisions issued throughout the United States ever year. Professional attorney-editors read each opinion and annotate it with individual abstracts, or headnotes, for each point of law it includes. The resulting annotated opinions are then passed in electronic form to classification editors, or classifiers, who read each headnote and manually assign it to one or more classes in the Key Number System. For example, a classifier facing the headnote: “Abuse of discretion in award of maintenance occurs only where no reasonable person would take view adopted by trial court assigned.” would most likely assign it to Key Number class 134k235, which as indicated in Table 1, corresponds to the Divorce subtopic “discretion of court”.
Every year, West Group classifiers manually classify over 350,000 headnotes across the approximately 82,000 separate classes of the Key Number classification system. Over time, many of the classifiers memorize significant portions of the Key Number System, enabling them to quickly assign Key Number classes to most headnotes they encounter. However, many headnotes are difficult to classify. For these, the classifier often invokes the WestLaw™ online legal search service, which allows the user to manually define queries against a database of classified headnotes. (WestLaw is a trademark of West Group.)
For instance, if presented with the exemplary “abuse of discretion” headnote, an editor might define and run a query including the terms “abuse,” “discretion,” “maintenance,” and “divorce.” The search service would return a set of annotated judicial opinions compliant with the query and the classifier would in turn sift through the headnotes in each judicial opinion, looking for those most similar to the headnote targeted for classification. If one or more of the headnotes satisfies the editor's threshold for similarity, the classifier manually assigns the Key Number classes associated with these headnotes to the target headnote. The classifier, through invocation of a separate application, may also view an electronic document listing a portion of the Key Number System to help identify related classes that may not be included in the search results.
The present inventors recognized that this process of classification suffers from at least two problems. First, even with use of online searching, the process is quite cumbersome and inefficient. For example, editors are forced to switch from viewing a headnote in one application, to a separate online search application to manually enter queries and view search results, to yet another application to consult a classification system list before finally finishing classification of some hard-to-classify headnotes. Secondly, this conventional process of classification lacks an efficient method of correcting misclassified headnotes. To correct misclassified headnotes, a classifier makes a written request to a database administrator with rights to a master headnote database.
Accordingly, there is a need for systems, methods, and software that not only streamline manual classification processes, but also promote consistency and accuracy of resulting classifications.